Corrupted screensaver frozen, can't be reset or navigated
My six-year-old Kindle DX has a corrupted screensaver image with a lot of random lines and patches of black and white, all frozen on the screen. When I use the navigation buttons, I can see things faintly happening in the background, but I can't see through the mess on the screen to read or do anything else.
Because of that, I can't switch Whispernet/wireless on, to upgrade the software, as Amazon has advised.
All efforts to reset the device, following Amazon's instructions, have failed.
Amazon technical support can't help; all they do is offer a tiny discount on a new, small Kindle which I don't want.
Is there any way, or anyone, to repair this otherwise-perfectly-good reader that I spent a lot of money for, back in 2010? I'm in New Zealand, but bought it in the USA.